Trump’s border wall will destroy possibility of the return of jaguars to Southwest

Emily Hartmann – Natural Resource Conservation

Jonathon Curreri – Building and Construction Technology

Matthew  Cornacchia – Natural Resource Conservation

Benjamin Morse – Building and Construction Technology

In 2011 scientists established a camera monitoring system in the Santa Rita Mountains of Arizona intending to capture imagery of mountain lions. After checking the tapes, the wildlife biologists discovered something they never could have imagined: a lone wandering jaguar. Excited, they rushed to set up more cameras throughout the area to observe this majestic and elusive animal. This spotted bachelor, named “El Jefe”, continually maintained a home in the mountains of Arizona for five years. His popularity in the media made him a local celebrity. After all, the mysterious Panthera onca species once roamed the deserts and mountains of the southwestern United States in New Mexico, Arizona, Texas and southern California but is now a rare sight. Unfortunately, the pressures on these populations due to human development and hunting caused the species to go extinct in the United States in the 20th century, with the remaining populations congregating in northern Mexico (Northern Jaguar Project, 2010). The range of the jaguar decreased by 40% due to anthropogenic effects. (Hunter, 2017) In recent years, conservationists observed jaguars wandering through the southwestern United States but none maintained a permanent residence. El Jefe gave conservationists hope that the species could return to the area and fully restore this precious ecosystem (Milberg, 2017).

An image of El Jefe, the US’s only wild jaguar, in the Santa Rita Mountains of Arizona. (Croke, 2016)

In late 2016, wildlife biologists released to the press that they had not observed El Jefe meandering through his mountainous home in months. They hypothesized that after the five years he spent roaming Arizona, he had reached sexual maturity and migrated to find a mate. The largest population of mating jaguars in North America lies just south of the international border between Mexico and the United States at the Northern Sonora Jaguar Reserve, so biologists’ best guess is that El Jefe migrated there. Conservationists have been eagerly awaiting the return of El Jefe and other individuals from Mexico to repopulate to the southwestern US (Milberg, 2017). The jaguar is critically endangered in the US with thousands of acres of protected habitat currently established in Arizona preventing the illegal hunting of this mysterious animal. However, following the election of a new president in the United States, the laws protecting the habitat for jaguars may be subject to dissolve after a push for the completion of the international physical border wall with Mexico (Davis 2017). A physical barrier between human territories has the capacity to sabotage the hope of the return of El Jefe and the entire species to the southwestern United States.

Walls already exist over 700 miles of the 1,954-mile border, reducing and isolating numerous rare populations of animals in North America (Gonzalez, 2017). Over 25 million acres of protected US public lands lie within 100 miles of the border. This includes six wildlife refuges, six national parks, tribal lands and wilderness areas (Barclay et al., 2017). The irreversible damage to jaguars and other fauna that would result from slicing through entire ecosystems with the completion of the border wall is immeasurable. In order to mitigate the threats to connectivity, gene flow and behavior of jaguars in the southwestern United States, the government should work closely with wildlife specialists to place corridors of virtual walls in specific areas rather than physical barriers.

The connectivity between lands is crucial for the jaguars’ ability to roam and find prey. 764,000 acres of the 25 million acres of US public lands is designated as critical habitat for the jaguar along the border.  Consequently, a physical barrier running the span of the border would effectively sever this contiguous land area (Davis, 2017).   Rosques et al. (2016) in their study of jaguar genetics concluded that this species heavily depends on large and well-conserved continuous habitat.  It is imperative that this species maintains a large home range due to prey density. The occupancy of a larger home range ensure that jaguars will have enough prey species to sustain populations. Hunter (2017) claims the completion of a border wall directly decreases the range of jaguars migrating between the US and Mexico in search of food.

Other major threats to the jaguar populations in the southwestern United States and Mexico due to the proposed wall are the detrimental health impacts caused by a reduction in gene flow. Gene flow is the transfer of genes from one population to another through immigration and breeding (O’Neil, 2012). A reduction in gene flow due to fragmentation, the separation of different populations of the same species, causes deleterious mutations that can reduce fertility or individual fitness.  Individuals with reduced fitness accumulate in small populations and decrease the chances of population survival (Couvet, 2002). Since small populations for the jaguar will receive detrimental health effects if we obstruct their gene flow, the question becomes will President Trump’s wall obstruct gene flow of the jaguar? Flesch et. al (2010) found that impermeable barriers, such as President Trump’s proposed wall, disrupt individual movement of desert bighorn sheep from population to population because they will not be able to cross the border, leading to a loss of genetic diversity. The ability to move freely between populations is vital for gene flow (Flesch et al., 2010).  This ability to move freely is equally important to the jaguar, as there are resident metapopulations, spatially separated populations of the same species that interact with each other, on either side of the United States border with Mexico (McCain & Childs, 2008).  These populations could fall victim to fragmentation when a large human development such as a wall occurs in their habitat. For example, interstate highways that have fenced barriers have caused genetic issues such as loss of biodiversity and accelerated genetic divergence (Flesch et al., 2010).  The construction of a border wall designed to halt the passage of humans will inevitably also stop jaguars, which will subject them to the detrimental health effects associated with a reduction in gene flow that lower individual fitness.

Detrimental genetic effects caused by a disruption in gene flow occur in other big cat populations, such as the Florida panther. Before the 19th Century, the Florida Panther had a home range that spread across the southeastern United States, but has since been reduced to a small area in Florida. Only small populations of this species exist today and consequently there has been a decrease in individual fitness.  Males suffer from cryptorchidism, which is when one or both testicles do not descend, which affects sperm quality and decreases their ability to produce offspring (Hedrick, 1995). Florida Panthers also suffer from heart defects and are susceptible to heavy parasite loads due to inbreeding (Gross, 2005).  Reducing the home ranges of jaguars in northern Mexico and the southwestern United States has the capacity to cause similar genetically induced health detriments.

A third threat to jaguar populations residing along the border comes with the adverse effects that artificial night lighting, which accompanies the physical border wall in the form of many large, diesel powered lights, has on wildlife behavior.  For hundreds of thousands of years, all of the life on planet earth became accustom to the night and day light cycle, and many animals rely on the cover of night time to travel, find food, and mate. Artificial lights severely reduce, if not eliminate entirely accessibility to the dark of night (Vande, 2015).  Bliss-Ketchum, Rivera, Turner, and Weisbaum (2016) conducted a study into the effects that artificial light at night has on animal movement patterns.  Bliss-Ketchum et al. (2016) concluded that both low and high amounts of light greatly affected various animal patterns. They found that black tailed deer decreased their passages through the monitored area from 14.1 per week to 4.15 per week under low light.  They also discovered massive effects on rodents, with passages decreasing from 11.62 per week to 1.0 in low light and an even lower .23 in high light conditions (Bliss-Ketchum et al., 2016).  Many crepuscular (animals that operate in between sunset and nighttime) and nocturnal animals recognize the threat of operating in the light, and drastically change their behavior. Researchers discovered through studying the effects of night lighting on small rodents, the common prey of large cats in the U.S.- Mexico border area, that the movement and activity of these animals ceased entirely when encountered with artificial light that exceeded the luminance of the average full moon (Grigone & Mrykalo 2004).  Also, when observing mountain lion behavior near artificial lighting, researchers saw they avoided the area completely (Grigione & Mrykalo, 2004).  These various studies prove that artificial light introduced to an environment has profound effects on many animals, from large cats down to small rodents.  Jaguars are a large cat species, which often times preys on small rodents; artificial light at night has been proven to at least affect the prey of the jaguar, and similar species of large cats to undergo behavioral changes due to artificial light at night. There is theory that artificial light at night has the potential to affect organism’s daily movements, migratory and reproductive behavior, and mortality rates (Gaston et al., 2015). These behavioral changes to the local wildlife will throw off the balance of many predator prey relationships, creating a more difficult ecosystem for various species to survive, especially jaguars.

Robbins (2011) argues that protecting predators, especially large mammals, is a critically important aspect of conservation due to their classification as apex predators. An apex predator can be defined as the animal that occupies the top tier of the food chain within a specific ecosystem. Since the jaguar is considered an apex predator, Dr. Luke Hunter, President of Panthera, claims their conservation is especially imperative because entire ecosystems hang in the balance (Garbutt, n.d.). The removal of predators has the capacity to cause subsequent effects on organisms occupying lower tiers of the system. A study of trophic cascades after the removal of wolves in Yellowstone National Park proved the benefits of the presence of predators. Trophic cascades are the effects that are observed lower down in the food chain as a result of the top predator’s removal (Carpenter, 2010). Following the reintroduction of wolves to Yellowstone, the ecosystem was able to observe an increase in biodiversity of flora and fauna.  Without wolves, elk populations skyrocketed, devastating the vegetation in this national park. Vegetation removal led to population strains on herbivorous species in Yellowstone, and so the wolves’ removal rippled through the food chain (US National Park Service, 2015). The reintroduction of wolves lead to healthy elk populations which in turn encouraged tree and plant growth. The restoration of riparian vegetation (the trees and plants lining a body of water) leads to the cooling of the rivers and therefore benefitted trout species that prefer cooler environments (Mayntz, 2017). The healthy trout populations prompted the return of species like beavers, amphibians, and different types of songbirds (Fraser, 2011). Conservation biologists hope that the reintroduction of jaguars in the southwestern United States will similarly increase the biodiversity of the southwestern United States (Northern Jaguar Reserve, 2010).

In order to facilitate the reintroduction of the jaguar, conservation biologists suggest the implementation of wildlife corridors to allow connectivity between the Northern Sonora Reserve and the southwest United States. A wildlife corridor can be defined as a protected piece of land that allows animals to pass from one area to another, without interference from humans and the developed world (Northern Jaguar Reserve, 2010). The creation of wildlife corridors along the border has the potential to solve many of the problems that jaguars will face with the construction of a border wall. These wildlife corridors normally connect similar habitats and allow animals to travel between areas, rather than having their travel routes blocked off by roads, cities, or walls. There is also a large movement to protect jaguars specifically through the use of wildlife corridors by the group Panthera (a conservation group that aims to protect the jaguar), including in Northern Mexico along the border in places such as Sonora (Garbutt, n.d.). Researchers have already predicted connectivity points with the highest probability of jaguar movement along the entire border, and it covers most of it, especially in Arizona and New Mexico (Schlyer, 2012). Wildlife corridors are already in use in North and South America. The Florida Panther is currently greatly benefitting from the creation of wildlife corridors in the southeastern United States. Through the creation of highway overpasses and tunnels, the Florida Panther was saved from the brink of extinction. These wildlife corridors ensured the connectivity of the species, and population persistence  (Robbins, 2011).  . In order to keep the connectivity for the species and better the possibility for its return to the United States, there should be wildlife corridors along the border that are kept free from a physical barrier and are monitored.

In today’s technology driven society, it is not unreasonable to consider a virtual solution to America’s border control problem.  After Trump’s executive order promising the construction of an expensive wall between the US and Mexico, a virtual wall became a popular consideration (Hanson, 2017).  Novak et al. (2016) explains that a virtual wall system utilizes infrared cameras placed in drones, blimps, and watchtowers to view what is happening in the cover of the night, rather than large powerful lights, eliminating the effects of night lighting on the local wildlife. Our goal is to encourage collaboration between conservation groups and the federal government in order to construct virtual fences in important wildlife corridors for the jaguar. The implementation of this virtual fencing in these specific areas will ensure the connectivity of regional populations. The introduction of the “Arizona Technology Plan” demonstrated the success of this system in small stretches of land between Arizona and Mexico. This plan was developed after the cancellation of SBInet in 2011, and included seven different types of programs to monitor Arizona’s border including Integrated Fixed Towers (IFT) and Remote Video Surveillance Systems (RVSS) (US Government Accountability Office, 2014 p. 2). The utilization of IFTs that are equipped with radar and infrared technology show the strengths of this border patrol system. The cameras that top these 80-foot towers are precise enough to distinguish between drug smugglers, hikers and wildlife (Novak et al., 2016). There are currently seven IFTs in operation since 2011, and at least 15 more are in the future works according to border patrol. These systems work best in largely rural areas so that the technology has the ability to function without glitches, due to the barren open land that allows video to identify people for miles (Pae, 2017). The introduction of a virtual fence along critical habitats for this specific jaguar species would not pose a significant threat to the persistence of these populations. The environmental assessment of this system concluded that a virtual wall would not have a significant adverse effect on the local environment, and is effective in border patrol (Pae, 2017). A virtual wall in these critical areas would allow jaguars to pass through unharmed, aiding in conservation efforts.

As far as economic feasibility, a virtual wall proves to be more cost-effective than Trump’s plans for a 30-foot physical wall spanning the entirety of the border (Dinan, 2017a). The pre-existing contract between Elbit Systems of America and the Department of Homeland Security makes them the probable choice for virtual fence integrations along the border. Their prices are around $850,000 per mile while a physical border would cost up to $25 million per mile (Dinan, 2017b). While the virtual fence will require extra funds to pay employees that will monitor the system, these funds could be allocated from those appropriated for the physical wall, as there is a much lower initial cost. In order for this wall to be financially achievable, part of the wall will have to be virtual anyway, according to defense experts (Harte, 2016). Americans working the border wall have not expressed a need for more physical barriers anyway. These workers argue that the necessity to improve border security include better equipment and monitoring services (Harte, 2016). Additionally, there are areas along the southern border of Arizona and New Mexico where physical walls are impossible to construct due to natural barriers. The use of technology in other strategic locations to ensure wildlife connectivity would not be a far cry from the pre-existing need for virtual walls in these areas. The government and border patrol working closely with wildlife conservation groups would allow the virtual wall to be effective.

In today’s fast paced technology driven world, it is more than reasonable to come up with a better solution to the immigration problem than finish constructing a physical barrier that people will still find ways around. As a nation, we need to be more conscious of the effects our development has on wildlife. A virtual wall along important habitats for jaguars in order to ensure species connectivity is a financially viable option and will allow a platform for the return of the species to the southwestern United States.


































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